Stamp-mill.



A PATEMTED MAY 2, 1905. No. 788,729' G. o. RICHARDS.

STAMP MILL.

` 4. APPLICATION FILED APR. 12, 190 2 SHEETS-SHEET l' No. 788,729. PATENTBD MAY 2. 1905. G. C. RICHARDS. STAMP MILL.

APPLICATION `FILED APR.12,1904.

mai L. my@ a 7x1 any@ ITED STATES Patented May 2, 1905.

PATENT OEEICE.

STAMP-MILL.

SPEGIFIGATIONd'orming part of Letters Patent N0. 788,729, dated May 2, 1905.

Application filed April 12, 1904. Serial No. 202,791.

To a/Z, whom it may concern:

Be it known that I, GEORGE C. RICHARDS, a citizen of the United States, residing' atOakland, in the county of Alameda and State or' California, have invented new and useful lmpro'vements in Stamp-Mills, of which the tollowing is a specification.

My invention relates to an improvementin stamp-millaand particularly in mills having mortars of the sectional type.

In the usual construction oi' mortars i'or stamp-mills the mortars are cast in a single piece, which is necessarily heavy, bulky, and diiiieult to transport, especially where such mortars are made to accommodate a plurality of stamps and where transportation is by packmule over rough mountain-trails. On the other hand, where it has been attempted to .construct mortars of the sectional type there has been difficulty, first, of getting a sufli ciently-rigid structure, and, second, of securing suitably-tight joints, both of these considerations being otl the utmost importance in a practical mill.

It is the object of my invention to provide a practical sectional mortar of simple construction wherein the sections may each be conveniently handled and which may be assembled into a rigid permanent structure having wa ter-tight joints. i

It consists of the parts and the construction and combination of parts, as hereinafter more i'ully described, having' reference to the aecompanying drawings, in which- Figure 1 is a vertical section of invention, showing mortars arranged in a battery. Fig. 2 is a plan view of central section. Fig. 3 is a side view of same with splash-board broken away, showing screen. Fig. iis a plan View o'l top section. Fig. 5 is a vertical section of same through ore-inlet. Fig. 6 is a vertical section of a base-section, and Fig. 7 is a similar view at right angles to that ot Fig. 6.

In carrying out my invention I may make the mortars to accommodate a single stamp or arrange them for a battery of two, three, or more stamps.

For purposes of illustration I have shown the invention applied to the battery type, the

only diflerence in this case from the singlestamp mill being in the size of the base-plate.

A represents a base-plate of suitable weight to withstand the shock ot the stamps and ci a size dependent on the number of stamps to be operated. As shown, the plate is formed with three integral annular projections 2 on its upper surface inclosing recesses to receive the usual dies 3. The bottoms oiE the recesses have the projecting bosses 2, which serve to hold the dies in place. A trough L is formed in the plate A relative to and encircling each die-recess,into which the splash from the stamp is reeeivedand directed at one side, as at 5, into the battery-box s, which lead to the concentrating-tables. he bottom oi the trough is inclined from a point opposite the discharge 5 to assist the outiiow. Seating solidly on the upper face of each of the projections 2 is an annular casting 6 in the 'form of a hollowT inverted truncated cone. This casting is formed with suitable openings for the reception of the segmental screens 7 A casting 8, constituting the third element of my mortar, seats on top ot each casting 6 and extends above and incloses the stamp 9.

The castings 8 have each a contracted neck portion extending upward around a stem l0, but out of contact therewith, and have each an ore inlet or hopper ll cast into one side through which material is fed to the inclosed stamp. rlhe upper and lower edges of the intermediate sections 6 are provided with suitable annular ribs or male members 12, litting corresponding1 grooves in the bottom oi the casting 8 and the top of the walls ot the dierecesses. Any suitable packing material may be placed between these meeting edges, so as to form a tight joint and prevent the escape .of pulverized material or mercury from the interior of the mortars. 1t is absolutely essential that these joints be tight. `Without some such means ot' interlocking the meeting` ends of the three sections a practical tight joint could not be had. '.lheintermediatesections 6 are preferably made annular, because the splash may then impinge with equal force on all the screens. These sections have each the annular base-flanges 13, which project over their respective troughs 4 and are adapted as aprons to direct the flow from the mortars into the recesses.

The solid portions of each casting 6 intermediate the screen-openings are provided with the downwardly-eXtending lugs or segmental projections 14, which engage the outside of the contiguous parts of the base to cooperate with the adjacent interlocking member 12 to give rigidity and strength to the mortar.

The screens seat on the ledges 13 and are locked in place by suitable means, as the keys 16, tting in grooves 15 in the sides of the screen-openings.

The three sections of a mortar-that is, the base, a section 6, and a section 8-are when assembled united into a perfectly rigid structure by means of the bolts 16', which are permanently secured at one end'to the eyes 17, cast or set into the base. The opposite ends of the bolts are threaded to receive the nuts 18 and it perforations in the base-flange 8of the casting 8. Sucha mill is portable, easily knocked down and set up, as light as is consistent with necessary strength, and is as rigid when set up as a mortar cast in a single piece. By dovetailing the sections any leak is practically impossible. It will stand up and withstand a great amount of jar and pounding even without the use of the tie-bolts 16', since the weight and the unitary character of each section are sutlicient to hold them together one upon the other.

Any suitable means may be employed to reciprocate the stamps to pulverize the ore.

If desired, segmental splash-boards 19 may be set in grooves in the walls of the screenopenings in the central castings to stay the splash and direct the pulp and water down into the troughs 4.

The ore is fed through a hopper 11 direct to a stamp, whereby it is pulverized to such lineness that it will eventually escape through the screens around the mortar. By this construction I am enabled to conveniently reduce the weight of the different parts of the mortar, so that these parts can be separately packed, especially'over difficult trails in the mountains, where the only means of transportation is on the backs of animals.

By reducing the number of parts oi' the mortar practically to three and casting these each as a unitary. structure I do away with the numerous joints that would exist in a mortar of a greater number of sections and at the same time get a sectional mortar possessing the utmost rigidity and stability.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-

1. A stamp-mill mortar made in three integral separable sections comprising a base with a central die-recess and a surrounding trough, a central section in the form of a hollow inverted truncated cone resting on the walls of said die-recess, said central section having screen-openings and an outwardly-extending base-flange overhanging the trough, an upper section resting on the central section and having a contracted neck extension and an integral hopper which extends into the upper portion of the central section, said sections having interlocking meeting ends whereby they may be assembled and held intact without the use of bolts or other securing means.

2. A stamp-mill mortar made in three integral separable sections, comprising abase with a central die-recess and a surrounding' trough, a central section in the formof a hollow inverted truncated cone resting on the walls of said die-recess, said central section having screen-opening's and an outwardly-extending base-flange.overhanging the trough, an upper section resting on the central section and having a contracted neck extension and an integral hopper which extends into the upper portion of the central section, said sections having interlocking meeting ends, and tiebolts having one end secured to eyes or rings in the top of the base and the otherto the up-V per section to unite the three sections into a rigid structure.

3. A stamp-mill mortar made in three integral separable sections comprising a base with a die-recess and a trough surrounding the recess, a central section having radially disposed screen-openings and seating on the base between said die-recess and trough, an upper section seating on the central section and having a contracted elongated neck to accommodate the stamp and also having anintegral hopper which discharges into the upper portion of the central section, said sections having interlocking ends whereby they may be assembled and held intact without the use of bolts or other securing means.

4. A stamp-mill mortar made in three integral separable sections comprising a base with a die-recess and a trough surrounding the recess, a central section having radially-disposed screen-openings and seating on the base between said die-recess and trough and having an annular base flange overhanging said trough, the walls of said screen-openings provided with integral guides for the reception ot' the screens and corresponding splash-plates, an upper section seating on the central section and having a contracted elongated neck and an integral hopper discharging into the top of the central section, said several sections having interlocking joints and tie-bolts having one end anchored to the base and the other to the upper section and extending outside the central section for holding the sections together in a rigid structure. Y

5. A stamp-mill mortar made in three integral separable sections comprising a base with a plurality of die-recesses and surrounding IOO IIO

IIS

'maree 3 I O tions havin g interlocking meetingl ends Whereby they may be assembled and held intact without the use of bolts or other securing means.

In testimony whereof I have hereunto set my hand in presence of two subscribing' Wit- I5 nesses.

GEORGE C. RICHARDS. l/Vitnesses:

S. H. NoURsn, Jnssin C. BRoDIE. 

